Paclitaxel, which is sold by the brand name, TAXOL®, is an anti-cancer (“antineoplastic” or “cytotoxic”) chemotherapy drug. Paclitaxel, a plant alkaloid, is used to treat breast, ovarian, lung, bladder, prostate, melanoma, esophageal, as well as other types of solid tumor cancers. It has also been used in Kaposi’s sarcoma. Paclitaxel is a natural product isolated from the Canadian yew tree bark. Removing impurities from Paclitaxel is particularly challenging, since the molecular structures in the extracted mixture are very similar. The crude solvent extract contains Paclitaxel and large quantities of highly polar taxane impurities.